Manages a pool of client connections and
is able to service connection requests from multiple execution threads.
Connections are pooled on a per route basis. A request for a route which
already the manager has persistent connections for available in the pool
will be services by leasing a connection from the pool rather than
creating a brand new connection.

ThreadSafeClientConnManager maintains a maximum limit of connection on
a per route basis and in total. Per default this implementation will
create no more than than 2 concurrent connections per given route
and no more 20 connections in total. For many real-world applications
these limits may prove too constraining, especially if they use HTTP
as a transport protocol for their services. Connection limits, however,
can be adjusted using HTTP parameters.

createConnectionOperator

Hook for creating the connection operator.
It is called by the constructor.
Derived classes can override this method to change the
instantiation of the operator.
The default implementation here instantiates
DefaultClientConnectionOperator.

releaseConnection

Releases a connection for use by others.
You may optionally specify how long the connection is valid
to be reused. Values <= 0 are considered to be valid forever.
If the connection is not marked as reusable, the connection will
not be reused regardless of the valid duration.
If the connection has been released before,
the call will be ignored.

getConnectionsInPool

Gets the total number of pooled connections for the given route.
This is the total number of connections that have been created and
are still in use by this connection manager for the route.
This value will not exceed the maximum number of connections per host.

Parameters:

route - the route in question

Returns:

the total number of pooled connections for that route

getConnectionsInPool

public int getConnectionsInPool()

Deprecated.

Gets the total number of pooled connections. This is the total number of
connections that have been created and are still in use by this connection
manager. This value will not exceed the maximum number of connections
in total.

Returns:

the total number of pooled connections

closeIdleConnections

Closes idle connections in the pool.
Open connections in the pool that have not been used for the
timespan given by the argument will be closed.
Currently allocated connections are not subject to this method.
Times will be checked with milliseconds precision
All expired connections will also be closed.

closeExpiredConnections

Closes all expired connections in the pool.
Open connections in the pool that have not been used for
the timespan defined when the connection was released will be closed.
Currently allocated connections are not subject to this method.
Times will be checked with milliseconds precision.